1. Field of the Invention
This invention generally relates to a bicycle front derailleur. More specifically, the present invention relates to a bicycle front derailleur having an outer casing receiving part disposed on a base member that mounts the bicycle front derailleur to a bicycle frame.
2. Background Information
Generally, a front derailleur is mounted to the bicycle frame adjacent to the front chain rings to shift a chain laterally between the front chain rings. A front derailleur includes a fixed or base member that is non-movably secured to the bicycle frame, and a movable member. The movable member includes a chain guide that is movably supported relative to the base member to move between at least two lateral positions. Typically, a linkage assembly is coupled between the base member and the movable member to movably support the chain guide. The chain guide typically has a pair of cage plates or guide plates arranged to selectively contact and move the chain between the front chain rings. The chain guide is usually moved relative to the base member by pulling and/or releasing a shifter control operation cable that is coupled between a shifter and the front derailleur. The control operation cable is often connected to one of the pivotal links to apply a torque thereto in order to move the chain guide between an extended position and a retracted position. Two examples of operation cable operated front derailleurs are disclosed in U.S. Pat. No. 6,093,122 and U.S. Pat. No. 7,081,058.